Flame spreader



March 16, 1937- G. A. HUETTEMAN ET AL 87 FLAME SPREADER Filed Aug. 23, 19:55

Patented .Mar. 16, 1937 PATENT OFFICE" FLAME SPREADER Gustav A. Huettcman and Joseph E. Leonard,

Oakland, Calif., assignors to Hammer-Bray Company, Ltd., Oakland, Calif., a corporation of Nevada Application August 23 5 Claims.

out impairing the'operating efficiency of the a burner or the heat transfer characteristics of the heater. As will be understood from the art, these burners, in their present highly perfected form, 15 produce a generally circular flame, while on the other hand, the preferred type of air circulating space heater, such as used within a room of a home or the like, is provided with a combustion or heating chamber which has a relatively great 20 width and a small depth. Attempts to combine these burners and heaters in the past by the use of flame spreader-s calculated to distribute the flame within the heating chamber have generally either resulted in a throttling of the burn- 25 er or an inefficient heating of the heater casing. An object of the present invention, therefore, is to provide a spreader of the character described which will convert the circular flame of a burner to an elongated flame such as will evenly 30 and intimately heat the walls of the combustion chamber without in any way imposing a serious restriction upon the burner and providing for the free issuance of the combustible gases therefrom.

Another object of the invention is to provide a flame spreader of the character described which will at all times provide for the inclusion of a stratum of air between the flame and the walls "of the spreader, whereby not only will the com- 40 plete combustion of the gases be insured at the sides of the flame and thereby avoid deleterious carbon deposits and ineflicient operation, but also the spreader itself will be maintained relatively cool and not subjected to the damaging effect of being placed directly in the flame.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following de-,

scriptionof the preferred form of the invention which is illustrated in the drawing accompanying and forming part of the specification. It is to be understood, however, that variations in the showing made by the said drawing and description may be adopted within the scope of the 55 invention as set forth in the claims.

, 1935, Serial No. 37,518

Referring to said drawing:

Figure 1 is a vertical sectional view of a heater and burner embodying a flame spreader as con- :tructed in accordance with the present inven- Figure 2 is a sectional view of the flame spreader and a portion of the burner and is taken substantially on the plane of line 22 of Figure 1.

Figure 3 is a cross-sectional view of the construction shown in Figure 2 and is taken substantially on the plane of line 3--3 of Figure 2.

Figure 4 is a plan view, shown partly in section, of theapparatus and is taken substantially on the plane of line 4--4 of Figure 3.

Figure 5 is a side elevation of the flame spreader of the present invention. v

The flame spreader 6 of the present invention, is illustrated in the accompanying drawing, with particular reference to Figure 1,, in operative position for use in conjunction with a liquid fuel burner 'l and an air circulating space heater 8. The burner 1, which may be of any suitable type, is here shown provided with a. housing 9 which is supported on the heater frame I l and forms what may be termed a volatilization chamber l2. Superimposed over the burner is a closed heating and combustion casing l3, whose front and rear walls l4 and I6 are relatively wide but spaced closely so as to define with the end walls I1 a chamber of considerable width but of small depth horizontally. As is common in this type of heater, an outer heater casing l8 forms a complete enclosure for the casing l3 and has its walls spaced from the inner casing so as to define air passages through which the air to be warmed may be circulated. The exit of products from the combustion chamber is afforded by way of the vent l9 which is connected to the top of the combustion chamber and extends through the back wall of the outer heater casing I8.

The burner housing 9, as shown in Figures 1 and 4, is relatively long and extends from approximately the end wall I! of the heater to adjacent the center portion of the burner casing l3. At the inner end of the burner housing, that is, the end underlying the central portion of the casing l3, there is provided in the top wall 2| of the I casing 9 an opening 22 surrounding which is a collar 23 which serves to direct the fuel volatil ized and mixed with primary air in the housing 9 generally upwardly therefrom in a cylindrical column. Concentrically aligned with but positioned over and spaced from the ring 23 is a ring 24, preferably formed integral with the bottom Wall 26 of the heater casing I6 and having an opening 2! which, together with the opening 22, defines the burner throat. The space between the rings 23 and 24 allows for the introduction of fresh air into the throat between the top and 5 bottom thereof for supporting combustion of the volatile fuel and air mixture rising through the opening 22 and the base of the burner throat.

It will be evident that in order to maintain burner efficiency, the burner should be kept relalO tively small and compact, but such burner would of itself be ill-adapted to heat up the long, wide side walls of the heater casing l3. Then, too, besides its size, the burner is arranged to produce a relatively high, generally circular flame, which is unsuitable for use in a heater of the type here shown. Previous attempts of combining a liquid fuel burner and an air circulating space heater,-

as here shown, by the use of flame spreaders or bailles or the like, have been unsatisfactory for 0 the reason that previous flame spreaders used presented too great a constriction to the flow of gases from the burner to allow the latter to function efllciently as a natural draft type, and generally entailed the impingement of the flame directly against the spreader whereby the same was not only subject to an intense disintegrating heat and oxidation, but also, in most instances, so constricted and cooled the flame as to produce relatively large carbon deposits, especially towards the ends of the spreader, which deposits, together with the aforesaid disintegration of the spreader, rendered its life entirely too short to be commercially successful. In accordance with the present invention, however, we have provided a flame spreader which will convert the generally circular flame of the burner to an elongated form for best heating the heater casing without presenting any substantial constriction to the free flow of the gases from the burner and without entailing the direct impingement of the flame against the spreader or the incomplete burning of the gases leading to the building up of the deleterious carbon deposits aforesaid. The spreader here shown comprises a hoodlike mem- 5 ber formed of a. pair of symmetrical half-sections 28 and 29, which are arranged to be bolted or otherwise secured together to define a conical base 3| arranged for positioning on the ring 24 and being generally circular in section thereat for 5 the receipt of the flame from the burner. The

sections 28 and 29 above the base 3| provide opposed side walls 32 and 33 which confine the flame therebetween and define between the spaced outer ends 34 and 36 thereof an elongated orifice 31 which'is extended from its ends 38, disposed adjacent but laterally spaced from the top of the ring 24, to an intermediate portion 39 positioned directly over in spaced relation to the top of the ring 24. As will perhaps be best seen from Figures 2, 3, and 4, the ends 34 and36 oi the side walls are terminated in generally parallelly extending flanges or lips 4| and 42, which define the orifice 31. These lips are widened from the intermediate portion 39 of the orifice to the ends 38 thereof so as to space the outer edges of the ends of the orifice a distance from the ring 24 substantially equal to the spacing of all other portions of the orifice. Also at the ends 38 of the orifice, the lips 4| and 42 are extended transversely to form end walls 5| and 52 which shield the flame issuing from the orifice at these points from the burnt gases in the heating chamber for a distance insuring the complete combustion of the fuel passing through the ends of the orifice. Thus, there is little or no tendency towards the forming of carbon deposits at the ends of the orifice in the case of the present flame spreader as has been the case in those-previously used.

Another important feature of the present flame spreader lies in the length, spacing and curvature of the orifice 31 so as to provide an effective passage area to the flame, substantially equal to the passage area at the top of the ring 24. As a result, there is substantially no constriction to the passage of the gasses through the flame spreader, and the natural draft characteristics of the burner are not interfered with.

It will be clear that the passage of the burning gases into the base of the spreader is generally parallel to the axis of the spreader at this point, while the issuance of the gases and flame from the orifice is substantially fan-shaped with the course of movement of the gas and flame, for the most part, inclined to the aforesaid axis. In accordance, with the present construction, this change in the course of movement of the gas is arranged to be effected in a portion of the spreader having an area expanded over that of the base of the spreader or the discharge orifice. Thus, notwithstanding the directional movement of the flame through such intermediate portion, the flame will not be forced to impinge against the walls of the spreader but rather the stratum of air issuing from the space between the rings 23 and 24 and surrounding the flame as the same enters the spreader is allowed to pass with the flame through the spreader and from the discharge orifice without being choked ofi'. This enlargement of the intermediate portion of the spreader is illustrated in the drawing and particularly in Figures 2 and 5, where it will be noted that the side walls 32 and 33 are bowed outwardly directly above the top of the ring 24 and especially do these side walls recede from the ring adjacent the ends 38 of the orifice. When viewed in a horizontal section, such as shown in part in Figure 4, the combination of this bowing of the side walls from the top of the ring 24 both longitudinally and transversely of the orifice defines in each side wall adjacent the ends of the orifice what may be termed expansion chambers or localized enlargements 43 which insure the passage of the gases to adjacent the ends of the orifice with a full supply of air for supporting complete combustion. Then, too, the receding of the side walls directly from the top of the ring 24 tends to draw the rising surrounding stratum of air into intimate relation with the side walls of the spreader and thereby, on the one hand, have an insulating and cooling action on the side walls, and on the other hand insure a complete combustion at the sides of the flame.

We claim:

1. A flame spreader adapted to be positioned over a substantially circular flame for spreading the latter into an elongated form comprising a member having a passage for said flame consisting of a circular portion for receiving the flame and terminated in a curved elongated orifice for discharging the flame, said orifice being substantially equally spaced at all points thereof from said receiving portion, and having the ends thereof substantially transversely aligned therewith.

2. A flame spreader of the character described comprising a hollow member provided with a circular opening at the base thereof for the receipt of a flame and having opposed side walls extending from said base and defining between the outer ends thereof an elongated discharge orifice, the

ends of said orifice being spaced laterally from said base and the orifice being curved to an intermediate portion positioned substantially across the axis of said base, the ends of said walls being formed in substantially parallel relation to provide opposed lips at said orifice, said lips being widened towards the ends of the orifice to space said ends a distance from said base substantially equal to the spacing of the intermediate portions of the orifice from said base, and means interconnecting said lips at the ends of the orifice and extending from said base to the outer edge of said orifice.

3. A fiame spreader of the character described comprising a member provided with a passage circular at the base thereof for the receipt of a fiame and having opposed side walls extending from said base and defining between the outer ends thereof an elongated discharge orifice registering with said passage, the ends of said walls being formed in substantially parallel relation to provide opposed lips at said orifice, said lips being widened towards the ends of the orifice to space all portions of the orifice substantially equally from said base, and means extending between said lips at the ends of the orifice and closing such ends from said base to the outer edge of said orifice.

4. A flame spreader of the character described comprising a member having a base with a substantially circular opening for receiving a fiame and provided with opposed side-walls extending axially and transversely from said base for confining said fiame therebetween and defining at the outer ends of said walls an elongated discharge orifice having, the ends thereof spaced laterally from and substantially transversely aligned with the end of said base opening, said side walls being formed with expansion chambers adjacent said ends of said orifice.

5. In combination with a burner having a circular throat for discharging burning fuel products and air, a flame spreader positioned upon said throat and having a curved elongated discharge opening formed with an intermediate portion spaced axially from said throat and ends substantially transversely aligned with the end of said throat.

GUSTAV A. HUETTEMAN. JOSEPH E. LEONARD. 

